In heating, ventilating and air conditioning (HVAC) systems for vehicles, there typically is provided a housing or duct system having an outside air inlet, an inside air inlet and an inside air outlet communicating with the passenger compartment of the vehicle, a blower for circulating airflow through the housing and various doors or panels with suitable controls operable by vehicle occupants for directing the flow of air through the housing and into and out of the passenger compartment. Air flowing through such systems typically is heated by a heater core positioned in such system housing and operatively connected to the engine cooling system, and is cooled by an evaporator core also provided in the system housing and operatively connected to the air conditioning system of the vehicle. Such core members essentially consist of heat exchangers and function to either impart or extract heat energy to and from air flowing therethrough.
To maximize heat exchange efficiency and eliminate airflow noise or "whistling" caused by air passing through the space normally provided between the periphery of the core member and the surrounding housing wall, it has been the conventional practice in the automotive industry to provide a peripheral seal in such space. Traditionally such seals have consisted of bulky, open cell foam materials compressed between the core member and surrounding housing.
The traditional type of seal used for sealing core members used in HVAC systems has been found to be unsatisfactory for a number of reasons. Such type of seal is susceptible to moisture accumulation which results in offensive odors contaminating air introduced into the passenger compartment of the vehicle. In service for prolonged periods, it may be subject to deterioration, developing air passageways through which airflow may flow and thus circumvent the core member, correspondingly reducing heat exchange efficiency. Such seals further require some form of adhesive for securing them to the core member during installation which not only adversely affects the installation time in the assembly of the components and installation of such systems in vehicles but further adversely affects the quality of such assemblies.
Accordingly, it has been found to be desirable to provide an assembly of the type described having a seal disposed between the core and surrounding housing which will obviate the aforementioned disadvantages of prior art seals and thus provide an effective and efficient heat exchanger assembly for a vehicle which will not provide any offensive odors or unpleasant noises causing discomfort to vehicle occupants.